During the latest ten years, development in the industry of machine tools has been growing rapidly in our country. Since industry automation is highly demanded, the study about CNC is therefore extensively proceeded. Owing to request for higher quality, the machine tool must achieve the high speed and high precision. There are three factors in precise motion control : the accuracy of reference command, the design of servo control structure, and machine structure. However the part of machine structure attains to maturity. The design of the control system need to include good motion control and correct reference command. NURBS can represent analytic curves and free-form curves accurately and easily. Cross-coupled control is able to adjust the dynamic system of each axis to reduce the contour errors. It is expected to improve control performance in terms of contour errors by combine NURBS reference command and the cross-coupled control framework. Keywords¡Gmachine tool, NURBS, cross-coupled control